#include <stdio.h>

int main()
{
    int a,i,b,n;
    printf("There are following friendly-numbers pair smaller than 3000:\n");
    for(a = 1;a < 3000;a++)
    {
        for(b = 0,i = 1;i <= a / 2;i++)
        if(!(a % i))
        b += i;
        for(n = 0,i = 1;i <= b / 2;i++)
        if(!(b % i))
        n += i;
        if(n == a && a < b)
        printf(" %4d..%4d",a,b);
    }
    printf("\n");
}